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对于形状比较复杂的费密面,普通的固体量子振荡频谱分析方法遇到了很大的困难,某些问题的研究工作(例如,Ⅳ—Ⅵ族化合物畸变相费密面的研究)因此而一度停顿。本文提出了一种双窗函数方法,成功地解决了Pb1-xSnxTe,SnTe等畸变相费密面的测绘问题,这种方法选用“强”、“弱”两种不同时窗函数,加在量子振荡信号上,分别进行频谱分析,从而最大限度地压低噪声水平,尽可能提高检测灵敏度的同时,又保证了较高的分辨率和较低的误差,对计算机模拟信号(由振幅不等的10个分量组成)的分析表明,最大频率误差不超过1%。The conventional Fourier transform methods were found to give an inadequately accurae and complete spectrum of the quantum oscillation frequencies for some materials with complicated Fermi surface such as IV-VI compounds in the distorted phase. Because of this problem, the early de Haas-van Alphen data of SnTe could not be interpreted properly. The ‘two window Fourier transform'technique was developed, and it solved this problem successfully in the Fermi surface measurements of Pb1-xSnxTe and SnTe. In this technique, the spectrum analysis are performed twice for each set of data by using two different windows, refered as ‘strong window' and ‘weak window' respectively, so as to increase the signal to noice ratio and to detect components with weaker strength and to resolve neighbouring components of similar strength. Hence higher detectability and resolvability and better accuracy can be achieved. The analysis results of the pseudo-SdH simulation signal, consisting of 10 components with different amplitude, show that the error in frequency of the spectrum is less than 1%.
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